Lack of effect of IFNγ on ¹²⁵I-rhIGF-I–specific binding to ECFCs. The plateau level of ¹²⁵I-rhIGF-I–specific binding was reached at a concentration of 0.4 nmol/L, and the level of specific binding in both the control (○) and rhIFNγ (•) groups was not significantly different. Scatchard analysis showed two classes of receptors, as previously published,26 but no significant change was observed after rhIFNγ treatment. A summary of triplicate experiments is shown in Table 3. ECFC purity in this experiment was 79% ± 4% in the control group and 76% ± 5% in the rhIFNγ group.